US3623039A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic tape system having mark code in the form of coincident absence of clock and presence of data pulses
Assignee: Individual
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Filing: 1970-05-08
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Granted: 1971-11-23
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Expires: 1990-05-08
Abstract
Abstract A recording system is disclosed for use in conjunction with a recording medium, e.g. magnetic tape, wherein the tape carries at least a clock channel and one data channel, and wherein data is defined in discrete sections along the length of medium. The system locates the sections by ''''mark'''' codes which precede each section and are followed by addresses that identify the sections. An absence of signals in the clock channel over a predetermined length of tape is one element of a ''''mark'''' code. The other element is provided by a coincident predetermined code signal in the data channel.
Inventors
- 👤 James E Barham
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 11:27
CPC Classifications
G; G11; G11B; G11B27/00
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
134 words
In a system for recording data, as on a magnetic medium, wherein data signals and clock signals are recorded in at least one data track and one clock track on said medium, and wherein data is defined in discrete sections along the length of said medium, which is sensed by movement relative to a sensing apparatus, the improvement for defining locations of said sections comprising: first means for sensing an absence of clock signals recorded in said clock track over a predetermined length of said medium, to provide a first signal; second means for sensing a predetermined signal in said data track coincidental with said predetermined length of said medium to provide a second signal; and means for indicating a defined discrete section of said medium upon coincidence of said first and second signals.
Claim 2
Dependent Claim
134 words
In a system for recording data, as on a magnetic medium, wherein data signals and clock signals are recorded in at least one data track and one clock track on said medium, and wherein data is defined in discrete sections along the length of said medium, which is sensed by movement relative to a sensing apparatus, the improvement for defining locations of said sections comprising: first means for sensing an absence of clock signals recorded in said clock track over a predetermined length of said medium, to provide a first signal; second means for sensing a predetermined signal in said data track coincidental with said predetermined length of said medium to provide a second signal; and means for indicating a defined discrete section of said medium upon coincidence of said first and second signals.
Claim 3
Dependent Claim
52 words
A system according to claim 1 wherein said medium carries address signals for said sections and wherein said system further includes a desired address register, a position address register for receiving said address signals upon coincidence of said first and second signals and means to compare the contents of said address registers.
Claim 4
Dependent Claim
31 words
A system according to claim 2 further including control means for controlling the flow of said data signals, said control means being connected to be controlled by said means to compare.
Claim 5
Dependent Claim
24 words
A system according to claim 1 further including means for receiving signals sensed from each track of said tape to provide two separate signals.
Claim 6
Dependent Claim
60 words
A system according to claim 4 wherein said separate signals are each provided by said sensing apparatus including a first amplifier for providing pulses upon receiving positive-going signal variations and a second amplifier for providing pulses upon receiving negative-going signal variations. 6 A system according to claim 1 wherein said predetermined signal comprises 1 1/2 cycles of said clock signal.
Claim 7
Dependent Claim
42 words
A system according to claim 1 further including means for recording said magnetic medium to accomplish an absence of clock signals in said clock track over a predetermined length of said medium and for recording a predetermined signal in said data track.
Claim 8
Dependent Claim
52 words
A system according to claim 7 wherein said medium carries address signals for said sections and wherein said system further includes a desired address register, a position address register for receiving said address signal upon coincidence of said first and second signals and means to compare the contents of said address registers.
Claim 9
Dependent Claim
31 words
A system according the claim 8 further including control means for controlling the flow of said data signals, said control means being connected to be controlled by said means to compare.
Claim 10
Dependent Claim
24 words
A system according to claim 9 further including means for receiving signals sensed from each track of said tape to provide two separate signals.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-11-22 | 1975-05-24 | 1975-11-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-11-22 | 1979-05-24 | 1979-11-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-11-22 | 1983-05-24 | 1983-11-23 | $7700.00 | Window Closed / Lapsed |